As suggested by a study presented at the ESMO 2014 Congress, biennial colorectal screening initiatives may increase the rate of high risk pre-cancerous adenomas diagnosis by nearly 90%. In Côte-d’Or, an initiative screening program began in 2003, and a group from INSERM Unité 866 in Dijon, France, was interested in how the rates of diagnosis changed as a result of the program.
Led by Dr. Vanessa Cottet, the team used data from patients diagnosed with a first adenoma between January 1997 and December 2008.
Of the studied patients, 38.7% had a high-risk adenoma (larger than 1-centimeter diameter polyp, villi involvement, or high grade of dysplasia). Before the screening (pre-2003), the rate of diagnosis was 136 per 100,000 people, and after the screening (post-2003), the rate was 257 per 100,000 people. Non-advanced adenoma diagnosis rates were 235 per 100,000 people pre-2003 and 392 per 100,000 people post-2003. These were percent changes of 89% and 68%, respectively.
Interestingly, diagnosis rate did not increase between 2005 and 2007. This may be attributed to a shift in testing from the common guaiac test to the immunochemical test, as the immunochemical test may be considered better than the guaiac test, even though colonoscopy is considered the gold standard for high risk populations in Germany and the United States. “Immunochemical fecal occult blood tests outperform guaiac tests for the detection of colorectal cancer and advanced adenoma,” explained Dr. Cottet in an ESMO press release. “They have doubled the detection rate of invasive colorectal cancer, mostly at early stages, and led to a fourfold increase in the detection rate of non-invasive colorectal cancer and advanced adenomas,” he concluded.
These fecal occult blood tests may be more efficient for detecting colorectal cancer than colonoscopy for high-risk patients, as suggested by another study from France in the laboratory of Dr. Sylvain Manfredi. In the region studied by Dr. Manfredi, fecal occult blood tests have been implemented for many years. “It is very important that public follows recommendations and participates in colorectal cancer screening programs,” stated Dr. Cottet. “Participation rate is a major issue for the success of such programs.”